#include <QCoreApplication>

/*int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    return a.exec();
}*/
#include <iostream>
using namespace std;
int main()
{
    //Длина окружности
    int diametr;
    cout<<"vvedite diametr"<<endl;
    cin>>diametr;
    cout<<"dlina okrujnsti="<<3.14*diametr<<endl;
}
